Abort TX May Generate Hot Switching.

Lasse SM5GLC

Now that CW works on my FLEX with the new f/w (2.12.0), it would be even nicer to have the hot-switching go away. The amp is keyed by "TX2" and then generates "TX req". Delay is set to 25.

If I use CWX and use one of the preprogrammed memories, and then push ESC to halt transmission, this often (but not always) generates a complaint from my amp (Acom 2000A) that it sensed a hot-switching issue.

Yellow trace: RF out. Blue trace: TX req on my Flex 6500 (TX2 passing thru the amp)

Looking at timing the keying signal into the amp the un-key is pretty much instant as the RF is inhibited (100 us) as I am looking at the KEY-out (needed pull-up for trig) from the amp, the keying timing is even tighter. It would be nice if the inhibit of key signal could be delayed a bit, 1 ms would probalbly be more than enough.

Remember this issue happens ONLY when aborting CW transmisson using memory.

Final note; the measurement was done with-out the amp running, and the hot switching may (or may not) be true i.e. RF is still active when the logic TX signal is dropped. As we are talking micro seconds, this may very well be the case, but a lot harder to catch IRL on the scope.

Ohhh, forgot to mention the timing of the characters are a bit off… spaces are a bit too short vs the dot and dashes… The faster you go the worse it gets. Easys spotted when scope was running :)

/Lasse SM5GLC